Parameter Design and Performance Analysis of a Saturated Amorphous Alloy Core Based Fault Current Limiter for Power Grid Applications

The traditional approach to reduce fault current over-duty is to upgrade protection systems or splitting busses in the substations. This upgradation in the substation may put extra financial burden on the grid operators. It also requires extended outages of the substations, which would reduce the reliability of the power system. To solve this problem a saturated amorphous alloy core-based fault current limiter (SAACFCL) can be applied. In this paper, parameters for the SAACFCL have been designed using a tuning process and characterized using advanced electromagnetic and electrical modelling. Also, the magnetic behavior of the core of the SAACFCL is analyzed using finite element analysis (FEA). Based on the characteristics obtained from the FEA, an improved electromagnetic circuit model of the SAACFCL has been developed. The mathematical model of the core's B-H loop has been included with the magnetic circuit model. The Ansys-Maxwell software is used to analyze the performances of the SAACFCL in the saturation and unsaturation states, such as the variation of the core saturation level with varying ac and dc current, the voltage drop across the ac and the dc coils, and the capability of the proposed SAACFCL to reduce the fault current. The simulation results validate the performance and characteristics of the SAACFCL during the varying conditions of its important operating parameters.